The role of RNA polymerase in gene selection during growth and sporulation of Bacillus subtilis is being examined. The two major approaches being used include the isolation and characterization of RNA polymerase from log phase and sporulating cells and the isolation and characterization of DNA fragments of B. subtilis containing promoter sites. The over-all plan is to examine the binding affinities for the RNA polymerases obtained from log phase and sporulating cells with the DNA fragments containing promoter sites and determine relative affinities of the enzyme for the promoters and also the specificity of the enzymes to the promoters. The enzymes are being purified and examined for their subunit compositions, activities on various DNA templates, and for their affinities to various DNA fragments. The role of vegetative delta factor on initiation of RNA synthesis is being investigated as well as its relationship with sigma factor during the initiation process. The sporulation delta-1 factor is being examined to see whether it confers sporulation gene specificity to the enzyme core. The successful isolation of DNA fragments containing promoters will depend on the use of suitable plasmids, proper selection techniques, and biochemcial identification of suitable promoter-containing DNA fragments. These studies should reveal whether a spectrum of promoter strengths occur, whether RNA polymerase specificity can be altered by small polypeptides found associated with the core during growth and sporulaton, and whether sporulation gene promoters are different from vegetative gene promoters.